#region Licence
// Copyright (c) 2007-2008 James Gregory (james@jagregory.com)
// All rights reserved.
// 
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
// 
//     * Redistributions of source code must retain the above copyright notice,
//     this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//     * Neither the name of James Gregory nor the names of its
//     contributors may be used to endorse or promote products derived from this
//     software without specific prior written permission.
// 
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
// THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#endregion

using System.Web.UI;
using System.Web.UI.WebControls;

namespace JAGregory.Controls
{
    /// <summary>
    /// An overriden BoundField that allows binding against hierarchical object structures
    /// commonly found in DALs, especially those provided by ORM frameworks.
    /// </summary>
    /// <remarks>
    /// If you try to use a standard BoundField with an hierarchical object structure, it won't be
    /// able to resolve the values correctly; try using MyObject.MySubObject.FieldName and watch it
    /// fail. This implementation correctly traverses of the hierarchy required for this kind of
    /// binding.
    /// </remarks>
    /// <example>
    /// Simple example using a two level object structure:
    /// &lt;jag:ObjectField HeaderText="Telephone Number" DataField="ContactDetails.TelephoneNumber" /&gt;
    /// </example>
    public class ObjectField : BoundField
    {
        /// <summary>
        /// Override for getting the value of a databound field.
        /// </summary>
        protected override object GetValue(Control controlContainer)
        {
            if (DataField.Contains("."))
            {
                // looking to bind against child-objects
                object component = DataBinder.GetDataItem(controlContainer);

                return DataBinder.Eval(component, DataField);
            }
            else
                return base.GetValue(controlContainer);
        }
    }
}